Outdoor power equipment includes such devices as mowers, trimmers, edgers, chainsaws, blowers, and the like. Although powering such devices could be accomplished in any number of ways, these devices are often powered by a gas engine or electric motor. The engine or motor connects to the shaft of a tool, such as a cutting blade or fan assembly, which spins to perform useful work. The operator can precisely control the engine or motor speed by manipulating a stepless trigger, thereby selectively controlling the application of power to the engine or motor as needed.
During operation, the operator may frequently wish to fix the speed of the engine or motor. For example, when mowing a lawn of uniform grass length or blowing off a driveway, the operator may wish to bring the motor or engine up to the desired speed and then use cruise control to maintain that speed for consistent results. For this purpose, gas or petrol blowers typically employ a cruise control function that is mechanically implemented to maintain engine or motor speed above or around a desired level. In particular, such functions may hold engine speed at a fixed RPM by blocking the trigger control mechanically in a fixed position with a lever that the user can operate. On electric motors, buttons with various steps are defined so that a discrete speed change is associated with each step. Thus, a desired speed can be achieved by proceeding to the corresponding desired step.
To improve operational control of the blower, it may be desirable to provide control functions that can limit the rotational speed of the motor in an easy and intuitive way and also provide a speed boost when desired.